Trailer crane for loading trucks



D. D. MQDERMOTT TRAILER CRANE FOR LOADING TRUCKS Aug. 23, 1949.

R H s O Y .T. E T .R e v e o e m W a A y M a m D S 5 Y Y B 7 4 9 l 3 l w N M d e l i F ug- 1949. D. D. M DERMOTT 2,479,758

TRAILER CRANE FOR LOADING TRUCKS Filed May 13, 1947 3 Sheets-Sheet 2 INVENTOR .D. .D. McDqznioZ 2.

BY M2. TQM-.1111

ATTORNEYS Aug. 23, 1949. D. D. M DERMOTT 231799758 TRAILER CRANE FOR LOADING TRUCKS Filed May 15, 1947 A 5 Sheets-Sheet 5 INVENTOR 11D. McDcrmo Z8 ATTO R N EYS Patented Aug. 23, 1949 s'rArE-s PATENT TRA LER CRANE. EOR LQAD NQ "Darwin *1). McDevmott, San Jose, lfiirlif.

Applicati n-Marla 1947, Seri l No. 341-666 'l l filairns. :1

This invention relates to, and .itis an object to provide a novel, trailer crane ,for loading tr k particlflarly garbage lwa ons'or the like- A lfHIthEI' -obiect of the invention .is to ,nrovide a trailer crane which is especially lusefuLin bane dling bundled garbage; it .being common ;practice :Eor garbage collectors to hundlelwas e paper etc. in .a .burlap sheet prior to loading on vthe truck.

Another object .of the vinvention is -..t o provide a trailer lcrane which comprises .a Wh e -Wi e trailer adapted to hitch [to the truck .at therear, and .a p ower actuated boom assembly adapted .to swing va ,load .from the ground at ,a noint ,to the rear of thetrailer upwardly,andforwardlytodi charge-saidload cntothe truck.

:An additional object .of this invention ,is Ito provide a tractor crane, as above, wherein the boom .is vactuated a loadin direction "Joy a gas, engine; there being means to automatically release the lead over the truck 'to disconnect the engine, andto return the boom to s'le 'l ap sition without attendance'hy the operator, whose only ltask therefore is initially connecting the enginejnloperajting relation to said'boom afterithe bun'dleis. attached .0 the same.

.'A further object of theinvention"istopro ride apractical and convenienttrailer-crane'for'loading trucks, and one which will be exceedingly effective fior "the purpose forwhich-it is "designed.

These objects are accm-1olished"*b -means of such structure and relative arrangement of parts es'wilPfiilly appear byta 'periisal df theiollow-lng specification and-claims.

In the drawings:

' 1 is a side :elevation of the trailer crane with theparts, iii-starting orioading position.

Fig.1 "is a similar view, but showsthe parts in full 'lines at load releasing position, and in dotted lines at an intermediate position.

Fig.3 "isa rearend elevationof thetrailer crane showing 'the parts in the position -of Fig. *2.

Fig. *4 isan enlargedfragmenta-ry sectional elevation of "the cable-drum -and -control"clntch assembiy.

Figf5-is-anenlarged "fragmentary plan view of said cable' drum and eontrokclntahassem-bly.

Referringmow more partioulafly *to the'eharactersl of reference on the -'drawings, the-trailer crane comprisesrarigidframe "I, -prov i; 'ied, ,at the rear, with a "transversely snaced pair pf rsupporting-ivheels"z; there b ng a tongue' t prolect-i ingjirom the front of saidfframel ionconnectjon byalliitch ."4 withralrear end of a truck 35 which .includesa body. 6.

wa e a te t pick '1 a e 1. 9 as a b llqle'lvof garbage qr'thelikfeir'firna-point to the rear i the trailer, and to swing said 'load forwardly and upwardly ;to discharge into the truck body *6 The mechanism e nplpyed to accomplish this result comprises the following-2 An upstanding frame, indicated generally at B, is fixegl on thetrailer framed adjacent its rear end, and includes upstanding sidebeams Genitahly corineoted-tg etherandbraced lac-rigidity the same.

A cross shaft I0 is journaled in connection with, anpl extend s betweemthe upper ends of the side beams 9, angle rotary boom 44 =is fixed, intermediateits endstoth'pross shaft It in radial relation.

The rotary 'boom -H is normallydnverted, 1. e. with the head endthereof lowermost, as :in Fig. 1, :and at ;such head end the boom is fitted with a laterally opening, generally :U-shaped load suspension frame 432% the latter being disposed wvith its outerf-ree end in substantially the sarne longitudinal vertical plane as the boom H.

l -he =load suspension frame 1.2 is normally disposed= in'sulostantiallyhorizontal,- rearwardly projecting relation adjacent :th-e ground, as in Fig. 1, for ready lmanual I access and the attaclnnent of the-load theretoi The load, as for example -a -bundle :iormed from a'burlap sheet' knottecltogether at the top, is attached to the load suspension frame 3 t2 means of a oha-in -13 at the outer --free end of said frame. "The chain 13 =is fixed to said outer free end of -tl=1e f rame 4 2, as at 44, the-nee is slipped through-the knot of the bundle 1, -and at lts othereend eal-d chain is :fitted with-an --eye ti whlch releasablyengagesovenaJnormaliylup standingrpin $6 adiiacent'thepoint of ehain connectionslfl.

Byi means of a poweressembly,hereinafter described, s the "normally a inverted =-rotary boom t I is swung from the starting positien'of'Fig. Amp warclly .aintil the end. or r aid :boom .is -.elevated, .-.as ein 2, -w-ith ethe load lsuspension frame .a-t2 proliectingeat ea forward sand inpwand incline over theltruck-sbody .6. alluring this course ohswingingmr moticnrafithe aboom; thetzbundle Lnependingsimmitheiload suspension l2, swi nses'd'lhmliglntheilatter.

Mis thearotar'y boom i I i -rcaches its upright -position, with the load suspension name -inclined upwardly a-n ddorwarcll-y, as -in"-Fig. 2,-over-the bcdy'u'i of the t r-nolggthe-eye*-5 automatically escapes-the pin "f6; which isthen pro j acting downawe rdlyqgbloyvfihorizontal; When ,this occurs the bundle I automatically slips away from the chain l3 and falls by gravity into the body 6.

The rotary boom is swung between its starting and discharge positions by means of a cable I! leading from a cable drum I8 on a driven cross shaft l9 carried in the trailer frame I ahead of the upstanding frame 8. From the cable drum I8 the cable |9 extends upwardly, in front of the upstanding frame 18; and. passes about an arcuate cable guide 20 on,- and projecting forwardly from, the normally upper end portion of the rotary boom I.

A clutch unit 2| is interposed between th driven cross shaft l9 and the 'drum l8, such clutch unit 2| including a clutch control arm 22 extending diagonally between actuating rollers 23 on a clutch control slide 24 having an operating handle 25 at one end thereof. An articulated link unit 26 is also connected between the slide 24 and a fixed point on the frame.

When the slide 24 is slid in a direction, by the handle 25, to straighten out the articulated link unit 26, the clutch unit 2| is engaged, whereby the drum I8 is rotated from the cross shaft I9. The cross shaft I9 is driven from an engine 21 by means of an endless chain and sprocket unit 28.

With rotation of the drum Hi the cable I! winds thereon and the rotary boom II is swung between its starting position of Fig. 1 and itsdischarge position of Fig. 2.

As said boom reaches its discharge position, a chain 29, connected between said rotary boom II and the articulated link unit 26, tightens and pulls upwardly on said unit, shifting the clutch control slide 24 in a direction to disengage the clutch unit 2|. Thus, the power means is automatically disconnected as the rotary boom reaches its discharge or dumping position. After this occurs the said rotary boom is returned to its normal starting or loading position, as follows:

Asthe boom approaches, but short of, its discharge position, a hook 30 on the normally upper end of said boom engages a crossbar 3| connected between a pair of forwardly projecting tension springs 32 anchored at theirfront ends to upstanding posts 33 on the trailer frame I; said cross bar 3| being flexibly suspended by cords 34 which lead to the side beams 9.

With continued swinging of the rotary boom towards its discharge position, with the hook 30 then moving rearwardly, the springs 32 are loaded in the manner shown'in Fig. '2. Thus, when the bundle or load discharges into the body 6 of the truck, and the chain 29 tightens and releases the clutch unit 2|, the loaded springs 32 act on the rotary boom II to swing it rearwardly beyond dead-center and start it on its downward swinging movement to its initial or starting position, as in Fig. 3.

In order to prevent too rapid lowering of the rotary boom on its return path of motion, there is provided a pair of hydraulic shock absorbers 35 suitably connected between arms 35 on the cross shaft l and brackets 31 on the side beams 9. These hydraulic shock absorbers 35 permit the rotary boom, together with the load suspension frame l2, to returnto its starting position easily and smoothly.

From the above, it willbe evident that once the operator has suspended a load 1 from, the suspension frame l2, and shifted the clutch conunit 2|, that the crane is thereafter automatically operative to swing the load to a position over the body 6; to discharge such load; to disengage the clutch unit 2|; and to return the rotary boom to its starting position.

While the trailer crane has been described primarily for use in loading garbage wagons, it obviously may be put to other uses to which it may be suited.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent are desired:

1. A truck loading crane comprising a main frame adapted to connect to the truck, an upstanding frame fixed on the main frame, a rotary boom mounted on the upstanding frame for swinging motion from a loading position with one end adjacent the ground to a discharge position with said one end over the truck, and power means operative to swing the boom between loading and discharge positions; a flexible element connected at one end to the boom, a pin on the boom, and an eye on the other end of the flexible element adapted to releasably engage the pin, said pin projecting upwardly when the boom is in loading position, and projecting downwardly when the boom is in discharging position.

2. A truck loading crane comprising a, main frame adapted to connect to the truck, an upstanding framc fixed on the main frame, a rotary boom mounted on the upstanding frame for swinging motion from a loading position with one end adjacent the ground to a discharge position with said one end over the truck, and power means operative to swing the boom between loading and discharge positions; there being a load suspension frame on the normally lower end of the boom projecting outwardly above the ground, said suspension frame being of generally U-shape and opening laterally, and means on the free end of said suspension frame to attach a load.

3. A truck loading crane comprising a main frame adapted to connect to the truck, an upstanding frame fixed on the main frame, a rotary boom mounted on the upstanding frame for swinging motion from a loading position with one end adjacent the ground to a discharge position with said one end over the truck, and power means operative to swing the boom between loading and discharge positions; there being a load suspension frame on the normally lower end of the boom projecting outwardly above the ground, said suspension frame being of generally U-shape and opening laterally, and means on the free end of said suspension frame to attach a load, the free end of said suspension frame being in substantially the same vertical plane as the plane of swinging of said boom.

4. A trailer crane comprising a wheel supthe ground, to a discharge position with said head end raised over the truck, means to releasably secure a load to said head end of the boom, and power means operative to swing the boom between loading and discharge positions; said powor means including a clutch driven cable drum on the trailer, and a cable leading from the drum to the normally upper end portion of the boom, there being a cable guide quadrant on said portion of the boom projecting forwardly and the cable engaging said quadrant.

5. A trailer crane comprising a wheel supported trailer adapted to be hitched to, and to trail behind, a load carrying truck, an upstanding frame on the trailer, a normally inverted boom pivoted intermediate its ends on the up standing frame for swinging from a loading position with the head end lowermost and adjacent the ground, to a discharge position with said head end raised over the truck, means to releasably secure a load to said head end of the boom, power means operative to swing the boom between loading and discharge positions, and spring means loaded upon swinging of the boom between loading and discharge positions operative to cause swinging of the boom from the discharge toward the loading position; the power means including a clutch unit, hand means to engage the clutch unit, and boom actuated means to disengage the clutch unit as the boom reaches substantially discharge position.

6. A crane, as in claim 5, in which said spring means includes a pair of transversely spaced tension springs anchored at one end and having a cross member between their opposite ends; there being a hook on the boom positioned to engage the cross member and load said springs as the boom swings toward discharge position.

7. A trailer crane comprising a, wheel supported trailer adapted to be hitched to, and to trail behind, a load carrying truck, an upstanding frame on the trailer, a normally inverted boom pivoted intermediate its ends on the upstanding frame for swinging from a loading position with the head end lowermost and adjacent the ground, to a discharge position with said head end raised over the truck, means to releasably secure a load to said head end of the boom, power means operative to swing the boom between loading and discharge positions, and spring means loaded upon swinging of the boom between loading and discharge positions operative to cause swinging of the boom from the discharge toward the loading position; the power means including a clutch unit, hand means to engage the clutch unit, and boom actuated means to disengage the clutch unit as the boom reaches substantially discharge position, there being shock absorbing means arranged to yieldably check swinging of the boom between discharge and loading position.

8. A trailer crane comprising a wheel supported trailer, means to attach the trailer to a load carrying vehicle, an upstanding frame on the trailer, a normally inverted boom pivoted intermediate its ends to the trailer, a load suspension frame on the lower end of the boom, said frame normally projecting outwardly from the boom in a substantially horizontal position whereby when the boom is turned on its axis through an arc of substantially 180 degrees the load suspension frame will then extend substantially horizontally out from the lifted end of the boom and overhang the body of the vehicle, and 75 35,932/30 means to swing the boom on its pivotal connection with the frame.

9. A structure as in claim 8 including a pin on the outer end of the load suspension frame which projects upwardly from the suspension frame when in its lower position, a flexible member fixed to the frame and an eye on the flexible member adapted to fit loosely over the pin.

10. A trailer crane comprising a wheel supported trailer, means to attach the trailer to a. load carrying vehicle, an upstanding frame on the trailer, a boom, a shaft fixed to the boom intermediate its ends, such shaft being journaled in the frame adjacent its upper end, a load suspension frame on the lower end of the boom, means to detachably suspend a load on the load suspension frame, means to rotate the boom to carry the suspension frame to a point overhanging the load carrying vehicle, a normally downwardly and rearwardly projecting arm on the shaft, a hydraulic shock absorber mounted on the upstanding frame to the rear thereof, the operating rod of the shock absorber being pivoted to said arm on the shaft.

11. A trailer crane comprising a wheel sup ported trailer, means to connect the trailer to a load carrying vehicle, an upstanding frame on the trailer, a boom pivoted intermediate its ends to the frame, a load suspension means on the lower end of the boom, a power unit on the frame, a driving shaft connected in driving relation with the power unit, a driven shaft, a cable drum on the driven shaft, a, lift cable connected between the drum and boom and operative to swing the boom on its pivot to carry the load suspension means from its lower position to a position overhanging the vehicle, a clutch unit between the shafts for connecting and disconnecting them in relative driving relation, a hand operated slide on the trailer, means connected with the slide and effective to engage the clutch parts when the slide is moved in one direction and to disengage the clutch parts when the slide is moved in the other direction, an articulated link connecting between the slide and frame and adapted to straighten out when the slide is moved to clutch engaging position, and a cable connected between the link and boom and efiective to break the articulated link and hence move the slide to de-clutching position when the boom is swung to carry the load suspension means from its lowermost position to its position overhanging the vehicle.

DARWIN D. MCDERMOTT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 852,919 Whittemore May 7,1907 1,052,096 Schulze Feb, 4, 1913 1,282,300 Senior Oct. 22, 1918 2,033,243 Jester Mar. 10, 1936 2,234,599 Johnston Mar. 11, 1941 2,390,268 Penney Dec. 4, 1945 2,426,889 Le Tourneau Sept. 2, 1947 FOREIGN PATENTS Number Country Date Australia Oct, 20, 1930 

